Lately, many electronic devices have evolved into mobile terminals that individuals can carry, and the functions of the electronic devices also have diversified. Accordingly, an electronic device has various functions for a user's convenience, and can activate functions according to a user's input to execute the functions. For example, the electronic device can provide various applications, wherein the applications can include an application for transmitting/receiving messages through a network, an application for acquiring images through a camera, an application for voice communication, an application for reproducing video, an application for receiving broadcasting signals to provide video or audio programs, and the like.
With diversification of applications that are provided by an electronic device, users' patterns in use of an electronic device are accordingly changing in such a way as to create and provide content using the electronic device from to receive and consume content using the electronic device. For example, many users share content produced by themselves through a Social Network Service (SNS). As representative examples, there are Facebook that provide a service based on personal lives, Instagram that provides a service of sharing pictures photographed by users, YouTube that is a service of sharing video created by users, and Blog that shares information about various matters of interest.
When content is shared, the shared content may be again shared by a plurality of users, or modified in such a way as to be modified or changed. However, in many cases, since an original author or a secondary author of the content is not known, it is difficult to protect rights of the original author of the content. For example, when a user acquires content without permission by downloading or screen-capturing it, and then manipulates the content in such a way as to modulate or modify it to share the modified content, the content is shared without any information about its original author so that the original author's rights cannot be protected.
Also, there is a case in which when an original author's original content is shared, the shared original content is modified by a plurality of users in such a way as to be modified or changed to create many modified content. In such instances, it is difficult to know which part of the original content was modified by what user.